A MasoSine SPS series pump from Watson-Marlow Pumps Group has transformed the efficiency and reliability of a bead mill at the Broadstairs facility of speciality ink producer, FSIS. The company previously used an air-operated diaphragm pump but had to battle constantly against excessive friction and heat which had the effect of curing a vital ink component – turning it from liquid to gel – ultimately leading to machine seizure.
FSIS is a global leader in the manufacture of speciality printing inks, producing high performance products for digital, flexographic narrow web and screen print that colour the images on thousands of everyday products – from retail displays, textiles and packaging to CDs and DVDs. The FSIS UK factory recently won “Best Process Plant Award” at the 2011 “Best Factory Awards” run by the Cranfield School of Management and Works Management Magazine, the purpose of which is to promote and reward manufacturing excellence in the UK in order to increase international competitiveness.
Over the course of the past decade, particularly in the past 3-4 years, changes in the wide format digital ink market have seen FSIS respond to maintain its position as a UV technology leader. Today, every process at the plant needs to be ultra efficient and 100% reliable in order to meet high customer demands.
“We have a bead/dispersion mill that effectively comprises a 6 litre capacity, water-cooled horizontal chamber,” explains the company’s Productivity Services Manager, Trevor Cornock. “Inside the chamber are a number of very small beads made of hard-wearing yttrium stabilised zirconium that measure 1.6-2.4 mm in diameter. These beads are deployed to grind the pigment being milled.”
Although this sounds straightforward enough, Fujifilm SIS encountered an unexpected problem that due to its repeated nature began to have a significant effect on productivity.
“A certain viscous ink component we use has a UV monomer type base that may cure when exposed to temperatures above 50C,” says Mr Cornock. “Because our previous AOD pump generated a fair amount of friction, this converted to heat and caused the ink component to turn from liquid to gel when temperatures exceeded 60°C, which would eventually bring the bead mill to a halt.”
Low friction solution
It was clear FSIS required a pump that generated minimal friction and so could avoid the associated heat problems. As an existing supplier to Fujifilm SIS formerly Sericol, Watson-Marlow was able to recommend a solution in the form of its MasoSine SPS series, a highly reliable and economical positive displacement pump for industrial applications. Its design features an exclusive sinusoidal rotor that overcomes the limitations of conventional rotary lobe pumps to produce powerful suction with low shear, low pulsation, gentle handling…and most importantly for FSIS, very low friction.
MasoSine SPS pumps offer capacity up to 91.2 m³/hr and pressures up to 15 bar, allowing typical services to include silicone, adhesives, monomers, polymers, latex, gelatin and resins. Initial trials on the viscous ink component at FSIS proved a resounding success. Incidentally, extensive validation tests were also required to ensure the process change at the 350-employee facility had no effect on its end products.
“The low shear nature of the MasoSine pump and its ability to cope with high viscosity proved to be a key factor,” says Mr Cornock. “Another major benefit is that the SPS pump is able to operate at very low flow speeds of around 30 rpm. This is important because if the pump has a high flow rate then the dwell time of the product in the machine is insufficient to be fully milled.”
The MasoSine pump has been installed for around nine months and FSIS reports no problems whatsoever. This is aided by the low maintenance design of the SPS series. With a single shaft and rotor, there is no need for the complex timing gears and multiple seals associated with conventional rotary lobe pumps. One rotor, one shaft and one seal equate to simple and economic maintenance.
Watson-Marlow Fluid Technology Group
Watson-Marlow Fluid Technology Group (WMFTG) er verdens førende inden for niche peristaltiske pumper og tilhørende væskebane teknologier til fødevare-, farmaceutiske, kemiske og miljømæssige industrier